Yamaha YZF-R125 Owners Manual: Motorcycle care and storage
Troubleshooting charts
Starting problems or poor engine performance
Starting problems or poor engine performance
Engine overheating
WARNING
Do not remove the radiator cap when the engine and radiator are hot.
S ...
Matte color caution
NOTICE
Some models are equipped with
matte colored finished parts. Be
sure to consult a Yamaha dealer for
advice on what products to use before
cleaning the vehicle. Using a
brush, harsh ch ...
Other materials:
Checking the rocker arms and rocker arm shafts
The following procedure applies to all of the
rocker arms and rocker arm shafts.
1. Check:
Rocker arm
Damage/wear Replace.
2. Check:
Rocker arm shaft
Blue discoloration/excessive wear/pitting/
scratches Replace or
check the lubrication
system.
3. Measure:
Rocke ...
Overheating
Engine
1. Clogged coolant passages
Cylinder head and piston
Heavy carbon buildup
2. Engine oil
Incorrect oil level
Incorrect oil viscosity
Inferior oil quality
Cooling system
1. Coolant
Low coolant level
2. Radiator
Damaged or leaking radiator
Faulty radiator cap
...
Checking the ignition spark gap
1. Check:
Ignition spark gap
Out of specification Perform the
ignition
system troubleshooting, starting with step 5.
Refer to "TROUBLESHOOTING" on page
8-3.
NOTE:
If the ignition spark gap is within specification,
the ignition system circuit is operating normally.
a. Disconnect the spa ...